Improvement in adding-machines



F. S. BALDWIN.

Adding-Machines.

Patented July 28 1874.

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UNITED STATES PATENT OFFICE.

FRANK S. BALDWIN, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO HIMSELF ANDGEORGE J. DU BOIS, OF SAME PLACE.

IMPROVEMENT IN ADDING-MACHINES.

Specification forming part of Letters Patent No. 163,522, dated July 28,1874; application filed April 1, 1874.

To all whom it may concern Be it known that I, FRANK S. BALDWIN, ofPhiladelphia, Pennsylvania, have invented an Improved Adding-Machine, ofwhich the following is a specification:

The object of my invention is to enable accountants and others to addlong columns of figures with rapidity and accuracy by the machine whichI will now proceed to describe, reference being had to the accompanyingdrawing, in which Figure 1 is a front view of the machine, partly insection; Fig. 2, a sectional View on the line 1 2, Fig. 1; Fig. 3, adetached view, partly in section 5 Fig. 4., an inverted sectional Viewon the line 3 4, Fig. 2, drawn to an enlarged scale; and Fig. 5, adetached view.

A is a metal plate, having a semicircular upper edge, a, described fromthe center of a short spindle, B, secured to the said plate, andcarrying a loose cogwheel, D, the latter being operated by aspring-pawl,a, on an arm, b,which is also hung loosely to the spindle,and which is provided with an index, F, the point of the latter beingarranged to traverse a graduated segment, 3 near the upper edge of theplate, and thus indicates the number of teeth which have been passedover by the pawl, or the extent to which the wheel D has been turned bythe latter. Stops d (Z on the plate A (indicated by dotted lines inFig. 1) limit the eX- tent of the movement of the pawl a to nine teethof the cog-wheel, and the yielding of the latter to the movement of thesaid pawl in the direction of the arrow 1 is prevented by a spring-pawl,e, secured to a stud, f, 011 the plate A, as shown in Figs. 1 and 3. Aboxlike casing, H, is hinged tothe plate A by a rod, h, secured to theopposite ends of the said casing, and passing through a tubularprojection, 9, of the plate, this hinge permitting the said casing to beturned back from the plate to a suflicient extent to disengage whicheverof its pinions J is in gear with the cog-wheel D, and to be then movedlongitudinally and turned inward toward the plate, in order to bringanother of its pinions into gear with the cog-wheel. The casing, whenadjusted, is prevented from moving longitudinally by a stop pin, i,secured to the spindle B directly beneath the center of the cog-wheel D,and adapted to any of a series of notches, j, in the edge of the casing11 directly above the centers of the pinions J. There are four pinionsin the present instance, marked, respectively, J, J J", and J", eachhaving ten teeth, and each hung to a spindle, K, which has its bearin gsin the casing, the spindles being arranged at equal distances apart fromeach other, and being also provided with numbering-wheels L, L L and L,which are prevented from turning accidentally by springrollers m, Fig.1, adapted to the notched peripheries of the said wheels, the latterhaving two concentrically-arranged sets of numbers, from 0 to 9inclusive, marked upon their faces, the said numbers, when the wheelsare turned, appearing successively through openings p and 10, formed inthe front plate of the casing H.

The pinions J, J, J and J and their numberin g-wheels, represent units,tens, hundreds, and thousands; and it is essential to the successfuloperation of the machine that, when the unit-pinion J is caused to makea complete revolution in the direction of the arrow by the wheel D, thetens-pinion J 1 shall make one-tenth of a revolution in the samedirection, and so on through the series, each successive pinion makingbut one-tenth of a revolution for every complete revolution of thepreceding pinion.

I attain this result without the use of intermediate pinions, andwithout appreciable lost motion, by causing one pinion to communicatemotion to another through the medium of a double-pivoted spring-pawl, P,which,

as will be seen in Fig. 5, consists of an arm, a, hung to the casing,and of a foot, n pivoted to the lower end of said arm, and acted on by aspring, M, which tends to maintain the point q in contact with the teethof the pinion to be operated on.

The heel g of the pawl is struck at the termination of every completerevolution of the preceding pinion by an arm, 1, of the lat ter, and isthus operated in a manner which will be readily understood on referringto Fig. 5.

Another important feature of my invention is the spring-lever S hung tothe stud f of the plate A, and extending into the casing H, where it isprovided with a spring-pawl, 1, (best observed in Fig. 3,) by which thepinion next in advance of that which is under the control of the wheel Dmay be turned to the extent of one-tenth of a revolution at a time, andfor a purpose which will be rendered ap' parent hereafter.

The operation of the machine will be best understood by following themovements required in adding a column of figures. Suppose, for instance,that the following numbers are to be added together: 345, 678, 812. Theparts are brought to the position shown in Fig. 1, and thenumbering-wheels L are so adjusted that a row of four noughts shallappear through the openings 1) in the casing H. The machine is then laidupon a desk or table, or directly upon the account-book or paper onwhich the numbers are marked, so that it can be moved up to the saidnumbers as they are added together.

The units column is first added by moving the arm 1), its pawl a, andindex F back and forth three times, the index being first moved to thegraduation 2 of the segment, and then back to zero, which will cause thenumber 2 of the first wheel, L, to appear through its opening 1) in thecasing, after which the index is moved to the graduation 8 and back, andfinally to the graduation 5 and back, which will complete the additionof the units column and cause the result, 15, to appear through theopenings 12 in the casing, the figure 1 of the latter number beingcarried to the tens column, or to the second wheel, L by the turning ofthe latter to the extent of one-tenth of a revolution through the mediumof the double-pivoted pawl P and arm 1 of the first pinion, J.

In order to add the tens column of the numbers given above, the hingedcasing H is drawn back and moved along the plate A in the direction ofthe arrow 2, Fi 1, until its pinion J is brought opposite the wheel D,with which it is thrown into gear by pushing back the casing, as beforedescribed. The index F is then moved back and forth to the graduations1, 7, and 4:, precisely as above described in connection with the unitscolumn, which will register the number 135 on the first three wheels, LL and L, as the result of the addition of the tens and units columns.The casing H is then shifted a second time, in order to bring the thirdpinion, J of the series into gear with the wheel 1), after which theindex is moved back and forth over the segment to the graduations 8, 6,and 3, which will complete the addition of the hundreds column and givethe total result, 1835.

The same operation can be continued to tens and hundreds of thousands bythe addition of other pinions and numbering-wheels to the machine.

The supplemental lever S and pawl t play an important part in addinglong columns of figures, as they obviate the necessity of moving theindex back and forth for every num ber, and of charging the memory withany result higher than units. For instance, in proceeding to add thenumbers 669, 878, 689, the parts of the machine are set at zero, asbefore, and are then manipulated as follows: Beginning with the unitscolumn, the accountant, knowing that 9 and 8 added together amount to17, depresses the lever S, and thus moves the tens wheel L to the extent of one tooth, and thus registers 10. The remaining 7 is added tothe 9 at the top of the column, which gives 16, of which 10 isregistered, as before, by depressing the lever S, and thereby moving thewheel L to the extent of another tooth, while the remaining 6 isregistered on the first wheel, L, by moving the index F to thegraduation 6 and back again to zero, the total result of the addition ofthe units column, amounting to 26, being thus obtained and registeredmuch more expeditiously than in the manner first described.

The casing H is next moved on the plate A, and the addition of the tenscolumn is proceeded with in precisely the same way, the results of thepartial additions being registered by the lever S and its pawl on thehundredswheel L and when the casing is again moved in order to add thehundreds column, the partial results are in like manner registered onthe thousandswheel L by the said lever and pawl.

The numbers which appear through the lower row of perforations p of thecasing are intended to give the results in subtracting one number fromanother, which, being merely the reverse of addition, can be readilyaccomplished by the machine.

In carrying out my invention the operating-arm b may, if desired, becontinued out to the graduated segment y, so as to form a pointer, inwhich case the index F can be dispensed with.

I claim as my invention 1. A calculating machine in which are combined aplate, A, with graduated segment 3 acog-wheel, D, and lever and pawl foroperating the same, and a train of pinions contained within a casing, H,by the longitudinal adjustment of which on the plate any one of saidpinions may be brought into gear with the cog-wheel, all substantiallyas and for the purpose set forth.

2. The supplemental lever S and its pawl t, combined with the pinions J,and arranged to operate on the latter in conjunction with the cog-wheelD, substantially as and for the purpose described.

In testimonywhereof I have signed my name to this specification in thepresence of two subscribing witnesses.

FRANK S. BALDYVIN.

Witnesses:

WM. A. STEEL, HUBERT HowsoN.

